Patellofemoral (Knee Cap) Reallignment

The kneecap (patella) rides in a groove in the lower end of the thighbone (trochlea of the femur) as a component of the knee joint. The patella can become unstable and either slip out of its groove (dislocation) or generate pain due to an excessive concentration of forces related to abnormal tracking. In most instances, rehabilitation to strengthen the muscles around your knee, along with the use of a supportive brace can effectively manage your symptoms and allow you to pursue your chosen activities. Occasionally, despite thorough conservative care, pain, swelling and recurrent instability will persist. A careful history helps to determine the cause, frequency, and the degree of disability created by your kneecap problem. Examination reveals knee range of motion, swelling, muscle atrophy and magnitude of the laxity of the patella. X-rays along with specialized MRI (magnetic resonance imaging) or CAT (computerized axial tomography) may be used to determine the exact nature of your patellar instability. When bony alignment is abnormal, the attachment of the tendon below the kneecap may need to be transferred to ‘straighten the pull’ through your patella to minimize the tendency for it to shift to the outside and partially dislocate (subluxate) or dislocate. During patellar instability episodes, the supporting ligaments on the inside of your kneecap (patellofemoral ligaments) may become stretched, incompetent, and no longer able to assist in stabilizing your patella. In that instance, a graft (most often from one of your hamstring tendons) is used to reconstruct the important ligament structures. Small tunnels are drilled on the inside of your thighbone and kneecap at very specific locations corresponding to the normal ligament attachments. The hamstring graft is secured in those tunnel locations. A brace helps to protect the surgical repair. Physical therapy assists you in regaining your motion and restoring strength to your thigh muscles. Full recovery may require up to 5 – 6 months.